I see that it was begun in the 1860s. If it was practiced then, it could well have been a continuous custom rather than a revival, although in my uneducated guess, doing it in Elul only is suggestive of revival, unless that was the vestige.

At a certain yeshiva in upstate New York, one of the rebbeim used to come through the dorm and yank the sheets off students who were sleeping at davening time. I've been told that one student put this practice to a stop by going to bed stark naked.